One of the most frustrating things for a newcomer to South Korea is getting a mobile phone and services. Majority of the foreigners are confused as to why their mobile phones from their home countries do not work in South Korea. The simple answer is that South Korea operates their mobile phones on the less universal CDMA as opposed to GSM which was adopted as a standard by most countries in Europe, Asia, and The Americas.

To make matters worse, the Korean CDMA frequencies differ from its North American counterparts. Korea operates in the 800 Mhz and 1800 Mhz band while North American CDMA providers such as Verizon and Sprint are on 850 Mhz and 1900 Mhz. The frequency differences do not pose much of a problem since majority of the new CDMA phone are multiband just like its GSM cousins. The problem lies in the fact that most CDMA phones until recently lack a SIM card. A CDMA phone has to be programmed at a service provider or phone dealer in order to get service.

The silverlining is that South Korean mobile phone operators SK Telecom and KTF have both adopted the the 3G UMTS WCDMA standard. So as not to get too geeky, this new standard is set to replace GSM. KTF and SK Telecom have been actively promoting 3G for the past few months which are branded as Show and T Service respectively.

This now allows foreign phones (Nokia, Ericsson, Palm Treos, HTC, Blackberries etc.) with global roaming activated from their foreign mobile phone providers to be used in Korea. The caveat is that your phone should be 3G WCDMA/HSDPA capable and you must be on a post-paid account with your provider. Why does it have to be a post paid account? Because pre-paid global roaming works a little differently. It’s based on a call back system. For example to call when roaming on a pre-paid account you dial a special prefix and the phone you want to call. You then hang up and wait for your phone to ring and upon picking up, the party you called will be on the other line and that doesn’t work in South Korea.

What about the rest of us who live in The ROK?

Now that South Korea is on the same page as the rest of the world as far as mobile phone standards, all we have to do is to buy a sim card from either SK Telecom or KTF and plug it into our foreign mobile phones right? Not quite, up until early this year the sim cards were locked to particular phone even within the same company, meaning it was not possible to take out the sim card out of your phone and put it into another phone. Even phones from the same Korean providers were sim locked, for example if I have an SK 3G phone with a sim and I decide to purchase a new phone from SK, it isn’t possible to just transfer my sim from the old phone to the new one.

The good news is that SK Telecom and KTF announced early this year that sim locks and phone locks would be disabled within their respective companies in the first half of 2008. Before the year ends we can expect to be able to swap SK Telecom sim cards and KTF cards, meaning no more SK or KTF specific phones.

Why am I so excited about all these developments, because I prefer PDA phones and smart phones of which I have little to choose from in South Korea, also because majority of mobile phone dealers are not keen on doing business with foreigners. When the time comes that all locks are removed then I can theoretically plug in an SK or KTF sim into a 3G Nokia, 3G Palm Treo or the much anticipated 3G iPhone which is rumored to be announced in the WWDC (Worldwide Developers Conference) this Monday. The removal of all the locks also opens up the possibility of having a pre-paid sim just like other countries. I’m sure that most expats and tourists will love to be able to use their own cell phones by buying a prepaid sim at the airport.